How to correctly mount wireless Access Points

Transcription

How to correctly mount wireless Access Points
How to correctly mount wireless Access Points
By Pranay Pancholi – Loughborough University – April 2015
1. Introduction
Over the past five years there has been a significant rise in the number of
wireless access points deployed within enterprise workspaces, enabling mobility
and support for new mobile devices such as smartphones, tablets and portable
laptops. As more users are now heavily dependent on using Wi-Fi networks, the
challenge is to ensure that wireless networks are optimized to meet user
expectations.
This document will provide some recommendations by installing wireless access
points (APs) correctly and provide simple methods to minimise any long-term
Wi-Fi problems.
2. Recommendations
AP Placement – Ceiling Mounted
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When mounting APs, how they are placed within their designated
environment is of great importance. In most enterprise locations, APs are
often installed on either false ceiling grids or attached onto mounting
brackets as shown below.
The access point is easily accessible by using standard A-frame ladders
for replacements or swap outs during any faults.
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Avoid mounting APs too high on ceilings. If mounted too high, gaining
access for replacement or maintenance purposes can be a problem, as
shown below. You may require a mini-tower to gain access safely and
that can be difficult to arrange.
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Models with internal antennas normally emit signals in a doughnut based
radiation pattern. If APs are mounted too high then a high percentage of
the signal can be lost before it reaches its desired area.
AP Placement – Wall Mounted
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Where possible, try to avoid mounting an AP flush against a wall, as most
of the RF output will not be serving its intended purpose. APs with
internal antennas are designed to be mounted on ceilings to provide 360degree coverage.
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There are solutions that enable APs with internal antennas to be mounted
correctly. Oberon manufactures various types of wall mounts that can be
used to mount APs onto walls.
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Alternatively you can use 6-inch corner braces to help secure an AP on a
wall. However this only applies if the manufacturer’s mounting bracket
holes line up with corner braces.
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There may be no choice but to mount APs high on ceilings. If so, it is
advisable to use external directional antennas to direct the signal to the
intended target area. The antennas should be installed in a vertical
orientation. Avoid having antennas mounted in a horizontal position as
this often reduces coverage.
Poor Installations
The photos below show some examples of poorly installed access points.
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Always try to avoid metal objects
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Avoid enclosing an AP by using a metal cage as in the example below
If a wall mounted AP requires protecting, then it’s best to use a plastic
Sarel enclosure and use the correct type of antennas as shown below.
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The AP should be securely mounted, ensuring that it cannot move about
or fall. Ensure APs are secure, level and keep as close as possible to user
areas.
Padlocks can be used to secure APs onto mounting brackets to stop any
APs being accidently knocked out of place and to reduce the risk of it
being stolen.
Padlocked AP
AP installed in the corridor area
In the above scenarios, the main users are behind the walls or partitions,
therefore the AP should be installed inside the office spaces rather than the
corridors. The APs are best served when close to end users, benefiting from
greater signal strength and higher connection rates.
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Try to avoid installing APs above suspended ceilings. The grid-work and
large metal objects such as ducts, containments and lighting all affect
signals and cause an increase in multipath. Although from an aesthetic
point of view the APs are hidden, it can cause problems for administrators
to try and locate them for any required maintenance.
Conclusion
It can be difficult for network administrators to provide a good wireless service
for the end users. It most cases this can be due to poor installation of APs as
described and illustrated above. To minimise problems, it is best to:
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Avoid placing APs in corridor spaces as Wi-Fi will become poor by the
time the signal reaches the client. Obstructions that will block the RF
include fire-doors, glass panels, bookcases etc. In order to achieve the
best possible user experience, install the APs as close to the users as
possible
Keep APs away from objects that will interfere with RF signal such as
metal objects that will cause issues with multipath
Ensure APs are mounted securely
Make sure APs have correct orientation when mounted and avoid wallmounting APs at 180°
Use antennas if required
Ensure you conduct a wireless site survey prior to installing. A site
survey will able to identify signal strength, existing RF presence, locate
dead spots, etc. Further information for conducting site survey can be
found by visiting: https://community.ja.net/groups/wtas-wirelesstechnology-advisory-service/document/ekahau-overview-site-surveys.
APs should be deployed based on the site survey
Understand what the user requirements are within the desired area.
Check what types of clients are needed to use Wi-Fi. Are clients using
smartphones, tablets or are laptops being used?
As for Ethernet recommendations - most APs will operate fine with CAT5e specified cabling. However for new cable installations CAT6a specified
should be used as this supports the 10GE standard.
By following the above best practices we are then able to provide a more
efficient wireless service as part of on-going wireless deployments. Due to many
building constraints it is important to work closely with facilities’ departments to
ensure any cabling or fitting requirements are met prior to installations.
Contact
Pranay Pancholi
Loughborough University
[email protected]